Acls And Multicast Packets - Cisco ME 3400 Software Configuration Manual

Using VLAN Maps with Router ACLs
Figure 31-7
Host A
(VLAN 10)

ACLs and Multicast Packets

Figure 31-8
packet being routed has two different kinds of filters applied: one for destinations that are other ports in
the input VLAN and another for each of the destinations that are in other VLANs to which the packet
has been routed. The packet might be routed to more than one output VLAN, in which case a different
router output ACL and VLAN map would apply for each destination VLAN.
The final result is that the packet might be permitted in some of the output VLANs and not in others. A
copy of the packet is forwarded to those destinations where it is permitted. However, if the input VLAN
map (VLAN 10 map in
Figure 31-8
Host A
(VLAN 10)
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
31-38
Applying ACLs on Routed Packets
VLAN 10
map
Frame
VLAN 10
shows how ACLs are applied on packets that are replicated for IP multicasting. A multicast
Figure 31-8) drops the packet, no destination receives a copy of the packet.
Applying ACLs on Multicast Packets
VLAN 10
map
Frame
Host C
(VLAN 10)
VLAN 10
Chapter 31
Input Output
router router VLAN 20
ACL ACL
Routing function
Packet
Input Output
router router VLAN 20
ACL ACL
Routing function
Packet
Configuring Network Security with ACLs
map
Host B
(VLAN 20)
VLAN 20
map
Host B
(VLAN 20)
VLAN 20
OL-9639-07